Research Paper
Seyed Mahdi Behinnezhad; Ghazanfar Shahgholian; Bahador Fani
Articles in Press, Accepted Manuscript, Available Online from 15 October 2021
Abstract
In this paper, a control method based on internal current control loop and dc link voltage regulator for three-phase photovoltaic (PV) system connected to the distribution network is presented. Current control method, the dynamics of the PV system separate it from the dynamics of the grid and the loads ...
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In this paper, a control method based on internal current control loop and dc link voltage regulator for three-phase photovoltaic (PV) system connected to the distribution network is presented. Current control method, the dynamics of the PV system separate it from the dynamics of the grid and the loads in it, and dc link voltage control improves control and increases the output power of the PV system. Also, a feedback control method is proposed to adjust the dc link voltage in order to improve the transient response of the PV system, which distinguishes the dynamics of the PV system from the nonlinear characteristics of solar cells and enables the design and optimization of system controllers in a wider range of workstations. In order to achieve a constant voltage level, a dc/dc converter is recommended to prevent the transfer of voltage harmonics to the inverter. The proposed method is investigated using a simulation of a PV system connected to the distribution network in the MATLAB software environment.
Research Paper
Mohammad Reza Yousefi; Amin Dehghani; Ali Asghar Amini
Articles in Press, Accepted Manuscript, Available Online from 20 November 2021
Abstract
In this paper, we propose a new multi-resolution wavelet based mesh free method for numerical analysis of electromagnetic field problems. In problems with variable object geometries or mechanical movements, the mesh free methods yield more accurate simulation results compared to the finite element approach ...
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In this paper, we propose a new multi-resolution wavelet based mesh free method for numerical analysis of electromagnetic field problems. In problems with variable object geometries or mechanical movements, the mesh free methods yield more accurate simulation results compared to the finite element approach in solving the inverse problem, because they are based on a set of nodes without using the connectivity of the elements. The wavelet based mesh free method requires effectively no local integration in the vicinity of nodes in numerical implementations. Moreover, wavelets give a more efficient approximation using multi-resolution analysis. On the other hand, boundary condition constraints are difficult to be applied on the wavelet based mesh free method. In order to apply boundary and interface conditions, we utilize a new form of jump functions in the set of basic functions. The boundary and interface conditions are applied effectively using the suggested slope jump functions. The simulation results of the proposed method using two different jump functions in solving some simple boundary problems are compared. The results are validated by analytical solutions. The results of this study can be used in future for inverse problem of Magnetic resonance electrical impedance tomography (MREIT) studies as an imaging technique for reconstructing the cross-sectional conductivity distribution of a human brain or body using EIT technique integrated with the MRI.
Research Paper
reihaneh kardehi moghaddam; akram sedaghati; morteza anbarsooz
Abstract
Ocean waves have an enormous amount of energy that can be converted into electrical energy using wave energy converters (WECs). Although it is difficult to estimate the amount of wave energy in the oceans and also extracting its power needs special facilities, this resource can provide a large part of ...
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Ocean waves have an enormous amount of energy that can be converted into electrical energy using wave energy converters (WECs). Although it is difficult to estimate the amount of wave energy in the oceans and also extracting its power needs special facilities, this resource can provide a large part of future energy because of the properties such as high energy density, low investment and high utilization. This paper investigates Improved Particle Swarm Optimization algorithm (IPSO) applied to a heaving point absorber wave energy converter to maximize the captured energy. The proposed algorithm is able to provide optimal parameter values and it also satisfies the physical constraints of controlling signals considering to simulation results. The simulation results illustrates the efficiency of proposed method in different sea statues and the comparison results show that the proposed method defines the power take of systems parameters in an effective way and maximize the extracted power of sea wave energy converters.
Research Paper
somaye Yaghoubi
Abstract
Approximately one half of the blood flow is made up of the Red Blood Cells (RBCs). Moreover, the geometry of the RBCs relative to the vessel diameter greatly effect on the physics and dynamics of the blood flow. It means the quantitative understanding through the vessels is important in multifarious ...
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Approximately one half of the blood flow is made up of the Red Blood Cells (RBCs). Moreover, the geometry of the RBCs relative to the vessel diameter greatly effect on the physics and dynamics of the blood flow. It means the quantitative understanding through the vessels is important in multifarious pathologies. To simulate RBCs, one of the modelling concerns is related to the details required for the sufficient accuracy and another is about the cost of computational methods. The mesoscopic models of RBCs combined both parameters accuracy and optimality. Then to achieve some of these goals in this study a numerical model called Low-Dimensional (LD) model along with DPD method are used to simulate Red Blood Cells, RBCs, in blood flows. LD-DPD model is developed due to new formulation of single particle in DPD and is able to capture the essential mechanics properties of these suspensions economically because of the low number of particles. The advantage of LD model is the use of spherical particles compared to the standard DPD which assumes point particles. For instance, in this study, to simulate a RBC, only10 colloidal particles are required. Also it is proved in this work different parameters are effective to determine the RBC radius and using this method, it is easy to investigate them until to match this simulation with the real one.
Research Paper
Pegah Shafaghi; Mehdi Mahdavian
Abstract
Power electronic converters such as dynamic voltage restorer (DVR), distribution static compensator (DSTATCOM), and unified power quality conditioner (UPQC) can zero voltage regulation, eliminate harmonics, reactive power compensation and unbalancing on both the source and load side of the system. The ...
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Power electronic converters such as dynamic voltage restorer (DVR), distribution static compensator (DSTATCOM), and unified power quality conditioner (UPQC) can zero voltage regulation, eliminate harmonics, reactive power compensation and unbalancing on both the source and load side of the system. The distribution static compensator is the distribution flexible ac transmission system (FACTS) device. It is an important device in a distribution network that used for maintaining constant distribution voltage, correcting power factor, and mitigating harmonics. This paper describes the application of a distribution static compensator for reactive compensation in electric distribution networks, to regulation voltage. Simulated performance of distribution static compensator is presented at varying conditions. The performance of the system has been considered for two cases: change in the source voltage (variable load is constant) and change in the load (voltage source is constant). At the end, the result of simulation with Matlab Simulink software has been presented. .
Research Paper
meraj rajaee; farima nasiri
Abstract
The increasing growth of urbanization and population and consequently the growth of traffic and movement of city residents with motor vehicles in and out of the city, cause many problems including traffic, air pollution, increasing greenhouse gases and environmental damages. This is while many in the ...
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The increasing growth of urbanization and population and consequently the growth of traffic and movement of city residents with motor vehicles in and out of the city, cause many problems including traffic, air pollution, increasing greenhouse gases and environmental damages. This is while many in the smart transportation industry are waiting to see how street experiences with less traffic and clean air can be transformed into sustainable change. The possibility of transportation innovation will be the most important option for this success. Electric bicycles are now considered as an alternative for car transportation in metropolitan areas. In this article, a new type of electronic bicycle is designed and manufactured. Due to the prevalence of the Corona virus in the world and the need to follow health protocols, a disinfection box for bicycle tracks is used. The door of this device will be opened and closed automatically in order to avoid the driver's hand colliding with the body of the device. For this purpose, the user or cyclist uses a special RFID tag and the power supply of this electronic bike is through solar cell technology.
Research Paper
iman pishkar; Amin Mirzakhani
Abstract
The electric car charging station, which is one of the infrastructure elements used to recharge electric vehicles (EVs), has not been developed in Iran. Therefore, in the present work a hybrid wind turbine-electricity grid system is simulated to supply electricity to an EV charging station in Bandar ...
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The electric car charging station, which is one of the infrastructure elements used to recharge electric vehicles (EVs), has not been developed in Iran. Therefore, in the present work a hybrid wind turbine-electricity grid system is simulated to supply electricity to an EV charging station in Bandar Abbas, located in the southern coastline of Iran. Technical, economic, environmental and energy surveys using HOMER software have been conducted over 25 years using NASA's website climate data. The use of 12 different types of wind turbines (horizontal axis, vertical axis and bladeless), many of which are not available in the software database and have been added to the database by the authors of the present work, has made the present work a comprehensive study in this field. The results showed that the Invelox wind turbine is very economical and its LCOE parameter is negative, but it cannot be used due to the high initial investment cost. The most economically viable wind turbine is the Generic 10 kW, which costs $ 0.023 per kWh of electricity generated. The most environmentally friendly wind turbine is the WES 5 Tulipo, which will reduce emissions by about 35 tons per year and has the highest amount of renewable electricity generation with 10% of the total electricity required by wind energy.
Research Paper
Behnam Asghari Beirami; Mehdi Mokhtarzade
Abstract
Hyperspectral sensors collect information from the earth's surface in the form of images with a large number of electromagnetic bands. Accurate classification of hyperspectral images has been one of the hot topics in remote sensing. Spatial information as a complementary source for spectral information ...
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Hyperspectral sensors collect information from the earth's surface in the form of images with a large number of electromagnetic bands. Accurate classification of hyperspectral images has been one of the hot topics in remote sensing. Spatial information as a complementary source for spectral information helps increase the classification accuracy of hyperspectral images (HSI). Local covariance matrix descriptor (LCMD) is the new spatial-spectral feature generation method for HSI classification. Although the LCMD is easy to use and performs well in HSI classification, it has some limitations, such as discarding the nonlinear relationships between features, which are useful in HSI classification. To address these issues, we propose a local kernel matrix descriptor (LKMD) for the classification of HSIs. In this study, the performance of LCMD is compared with LKMD with two widely used kernels, RBF and polynomial, and final classification results on two real HSIs, Indian Pines and Pavia University, proved the superiority of LKMD over LCMD.
Research Paper
Mashallah Valikhani Dehaghani; Mohsen Khalili Samani; Daryosh Mohamadi Janaki
Abstract
The impact of administrative processes on energy services is significant. Since electricity is considered the center of development, special attention to rural electricity supply and also solving possible problems of important rural centers in the areas of reliable electricity supply and lighting can ...
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The impact of administrative processes on energy services is significant. Since electricity is considered the center of development, special attention to rural electricity supply and also solving possible problems of important rural centers in the areas of reliable electricity supply and lighting can pave the way for sustainable development in rural areas. In this regard, one of the main priorities of the government is to provide services to villages, hamlets, and deprived areas, as well as increase the quality of services provided to these areas and, of course, for sensitive uses in the villages. Due to the importance of the above, in the present work, for the first time, the simultaneous production of solar electricity and heat for a public health center located in the village of Sar Agha Seyed in Chaharmahal and Bakhtiari province has been evaluated. The reason for choosing this village and this government health service center to investigate is that in winter and autumn, with snow and rain, the region's electricity is cut off. In addition, it is very important and necessary to pay attention to continuous and stable electricity supply due to the sensitivity of medical centers in providing services. Technical, economic, environmental, optimization, and sensitivity analysis assessments are performed by HOMER commercial software over a period of one year. Another purpose of this article is to study the different organizational dimensions of the use of renewable energy in rural public health centers
Research Paper
Mohammad Kazemi Bidhendi
Abstract
The feasibility of direct use of photovoltaic energy to supply cooling demand of a building is investigated at a demonstration site through its design, installation and evaluation. The cooling is accomplished by using a novel method of energy supply, including photovoltaic panels, electrically driven ...
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The feasibility of direct use of photovoltaic energy to supply cooling demand of a building is investigated at a demonstration site through its design, installation and evaluation. The cooling is accomplished by using a novel method of energy supply, including photovoltaic panels, electrically driven solar-assisted heat pump, in-house developed inverter and thermal energy storage system.
The refrigeration unit is based on a variable speed heat pump, which is supplied by direct current (DC) from photovoltaic panels. In order to provide appropriate current and voltage with high energy transform efficiency, a novel inverter is developed. While in conventional systems four energy transform stages are needed to supply a variable speed heat pump, by this method conversions are reduced to two. In addition, a modular structure of the inverter improves the transformation efficiency, particularly in partial load condition. Although, using this technology reduces the number of energy transformations and losses, but intermittency and variability of PV power will be transferred to the heat pump and the cooling power accordingly. Therefore, a kind of energy stabilizer system is necessary to control the energy fluctuation. Hence, a 30 m3 water tank is used as the thermal energy storage system.
The heat pump can be fed simultaneously by both PV and grid power through two separate interfaces. Thus, no additional backup system is needed.
